VFR Tower Vis Sep

At what point does a VFR tower apply visual separation for successive IFR arrivals?

Is it possible to be other than one-in-one-out for successive IFR arrivals?

Does this need to be in an LOA?

If not in an LOA, can this be authorized in a pinch?

It just seems like a grey area for when center responsibility for IFR separation ends, and tower begins.

Curious about input from tower guys...

Looking at .65 5-9-5 Approach Separation Responsibility

a. The radar controller performing the approach control function is responsible for separation of radar arrivals unless visual separation is provided by the tower, or a letter of agreement/facility directive authorizes otherwise. Radar final controllers ensure that established separation is maintained between aircraft under their control and other aircraft established on the same final approach course.

NOTE-
The radar controller may be a controller in an ARTCC, a terminal facility, or a tower controller when authorized to perform the approach control function in a terminal area.

Combined with .65 7-2-1 Visual Separation

c. Nonapproach control towers may be authorized to provide visual separation between aircraft within surface areas or designated areas provided other separation is assured before and after the application of visual separation. This may be applied by the nonapproach control tower providing the separation or by a pilot visually observing another aircraft and being instructed to maintain visual separation with that aircraft.

Re: VFR Tower Vis Sep

So... the sector controller has multiple inbounds, and tower hasn't called a downtime on a particular aircraft that led the sequence.

Originally Posted by BeaconSlash

Is separation legal if the sector calls the tower and asks if they can provide visual separation between N12345 and N45678 (before radar separation is lost), and they reply with yes?

yes it's legal, as long as the tower is already talking to the first guy. you need to be talking to at least one to provide visual separation.

by saying "yes" you have told the "center" or approach controller that you visually have both aircraft in sight out your window and will provide visual separation from that point on, in lieu of standard radar separation. note: visual separation cannot be used in lieu of wake turbulence separation. if you have a wake turbulence separation issue then the "center" or approach controller is still responsible for those miles unless the PILOT sees the bigger guy and accepts visual separation or is told to follow.

Originally Posted by BeaconSlash

Can an LOA define an area/distance in which tower will provide visual separation between successive arrivals? Assuming so, how would that look?

yes. ours (L30-Las Vegas approach) with HND (Henderson Tower) says tower will provide visual separation between successive arrivals within 10 miles of the airport below 7,000. basically for us, we run the first guy in and HND will provide visual when we run the second guy in. it's on the approach controller to calll down to HND, or HND will normally take the initiative, to let the approach controller know when the tower has both in sight and will begin providing visual separation.

Originally Posted by BeaconSlash

Does FAA ATCT vs Contract make any difference with any of this?

No! in fact, contract controllers will usually be more liberal with this application because they generally have less performance management (no snitches) and contract controllers are experienced tower controllers. not that FAA towers are not, but there are a ton of new people in FAA towers.

Re: VFR Tower Vis Sep

Originally Posted by BeaconSlash

Though that's .65 phraseology, I don't like that in a grammatical sense.

So the approach control provider "approves" it... who says it's actually being applied?

If the center or approach control approves visual separation it's the responsibility of the tower controller to make sure that requirement is met. I can approve visual separation all day long with the tower we deal with, but it's their responsibility to ensure that the visual separation is being applied correctly.

Re: VFR Tower Vis Sep

All above is excellent, couldn't agree more. All I would add is if you go to the trouble of modding an LOA for arrival vs. arrival visual sep, you should also do arrival vs. departure visual sep in the same document. You can add any particulars needed for your and center's unique situations. Done right, you can speed things up in a safe manner.

Lastly, most LOAs I've seen have a clause that just about anything can be coordinated real-time. It just has to be legal.

Re: VFR Tower Vis Sep

Originally Posted by MichaelGraham

The center/approach controller should probably say the standard phraseology "Visual separation approved between (a/c) and (a/c)."

don't confuse this phraseology. it's for arrival/departure, not arrival/arrival. SYD is not the same as tower providing visual separation between two arrivals that may get closer than required radar separation.